Hi Shelley,
I'm not sure on specifics of iron supplementing effects, but here is some info on Protein foods and absorption/timing of C/L meds.

[The medication levodopa (Sinemet) is a protein building block so it competes for absorption with other proteins. Eating a very proteinic meal reduces the likelihood of effectively absorbing levodopa, so you may want to leave meat, fish and cheese for dinner and eat more carbohydrates and vegetables during the day. Taking medication on an empty stomach – 30 minutes before or 60 minutes after a meal – allows the drug to reach the small intestine and absorb faster. However, a carbohydrate snack (crackers, toast, oatmeal) with the medication may be necessary to prevent nausea.]
Parkinson's Disease | Good Nutrition for Parkinson's Patients - More Details